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A multi-level process for policy design and integrated planning
No full textThe 'Shared Water Policy' (PEP (Politique de l'eau partagée)), it is the result of a broad participative process that involved around 1 in 600 New Caledonians. This chapter presents the multi-level participatory procedure implemented for the development of this policy, over a 2-year period. It focuses on the process, method¬ology and tools used to support policy design. It discusses the interests and the limi¬tations of this process in terms of including customary values and norm
First record of Neocardiochiles (Hymenoptera: Braconidae) parasitising Stenoma decora Zeller, 1854 (Lepidoptera: Depressariidae), with description of a new species
No full textStenoma decora Zeller, 1854 (Lepidoptera: Depressariidae), is considered a pest of the cacao tree, Theobroma cacao L. (Malvaceae), causing direct losses by damaging the fruits. In this study, we searched for parasitoids of Stenoma decora. Caterpillars were obtained from fruits and stems in commercial plantations of T. cacao in Mutuípe, Bahia, Brazil, and reared in laboratory. Here we describe the new species Neocardiochiles tropicalis sp. nov. (Hymenoptera: Braconidae) as a parasitoid of S. decora. Parasitised individuals can be readily identified, as the parasitoid kills the prepupa and produces a light-coloured silk cocoon in place of the host's dark, sclerotised pupal exuviae. This is the first species of the Neocardiochiles recorded in Brazil, and the southernmost record for the genus so far. The presence of this parasitoid in a commercial crop area provides an important context for biological control, representing a new perspective for the management of S. decora
Species distribution modeling to predict tsetse fly (Glossina spp.) habitat suitability in Kenya
Get PDFBackground: African animal trypanosomosis (AAT) and human African trypanosomosis (HAT) are transmitted and spread primarily by tsetse flies (Glossina spp.) in sub-Saharan Africa. The animal disease poses significant challenges to agropastoral systems, including in Kenya, where 38 out of 47 counties are infested with eight species of Glossina. Climate change and human activities can also aggravate these infestations, putting rural-scale farmers who rely on agropastoral systems at a greater risk. Geographical gaps in existing entomological datasets limit a comprehensive understanding of tsetse fly distribution across the country, especially amid rapid landscape dynamics. Methods: This study aimed to predict the spatial distribution of tsetse flies habitat in Kenya using recent entomological data (i.e., tsetse fly occurrence records), satellite-derived environmental variables, landscape structure, demographic indicators, and species-distribution modeling techniques. We applied four machine learning (ML) algorithms—random forest (RF), support vector machines (SVM), maximum entropy (MaxEnt), and generalized linear models (GLM)—to predict tsetse flies habitat suitability. Additionally, we developed ensemble models that combine the predictive power of the four algorithms. Predictions were made at the genus level (Glossina spp.) and the species level for one priority species (Glossina pallidipes). Results: The models performed well with true skill statistic (TSS) and area under the curve (AUC) metric measures of 0.67 and 0.88 for Glossina spp. and 0.85 and 0.96 for G. pallidipes, respectively. The predictions indicated an estimated potential suitable area of about 26% of Kenya for Glossina spp. and 9% for G. pallidipes. Tsetse fly habitat suitability was positively correlated with increased sheep density, normalized difference vegetation index, and soil moisture. However, suitability declined when the maximum land surface temperature (LST) exceeded 40 °C and elevation increased above 400 m. Conclusions: These findings can help improve the targeting and, hence, the cost-effectiveness of surveillance and ultimately support an evidence-based progressive control of tsetse flies infestation in Kenya
How do host age and nutrition affect density regulation of obligate versus facultative bacterial symbionts? Insights from the tsetse fly
Get PDFHost-symbiont relationships can vary tremendously in the extent to which hosts depend on and control their symbionts. Obligate symbionts that provide micronutrients to their host are often compartmentalised to specialised host organs and depend on their hosts for survival, whereas facultative symbionts retain the ability to survive outside of their hosts. Few studies compare the extent to which a host controls and adjusts the density of obligate and facultative symbionts directly. We used tsetse as a model for teasing apart the relationships between a host (Glossina morsitans morsitans) and obligate (Wigglesworthia glossinidia) and facultative (Sodalis glossinidius) symbionts. We hypothesised that tsetse actively regulate the density of Wigglesworthia according to the host's requirements, depending on their current nutritional state and developmental age. In contrast, we postulated that Sodalis retains some independence from host control and that the growth of this symbiont is dependent on the conditions of the immediate environment, such as nutrient availability. Using qPCR, we examined how symbiont densities change across host age and the hunger cycle. Additionally, we investigated how host nutrition influences symbiont density, by comparing tsetse that were fed nutrient-poor or vitamin enriched diets. We found that the density of Wigglesworthia was not influenced by the nutritional status of the host but reflected long-term host nutritional needs. In contrast, the density of facultative Sodalis depended on the nutrient availability. We propose that tsetse tightly regulate Wigglesworthia but exert only partial control over Sodalis growth due to the relatively recent transition of this symbiont to host-associated living
Fiche N° 7 : renforcer le système d'innovation agricole (SIA) de la filière laitière en Itasy
Get PDFTowards systemic support for agricultural mechanization in sub Saharan Africa
Get PDFAgricultural mechanization and motorization play an important role in reducing the arduousness of work and contributing to food security. In sub-Saharan Africa, there remain many challenges before equipment becomes accessible to as many people as possible, is properly used and maintained, and deployed in an inclusive and lasting manner. Existing equipment is sometimes ill-suited, and there is a lack of information about access to mechanization and associated agricultural practices, as well as appropriate ways of intervening. Yet, some novel courses of action do exist, promoting systemic intervention incorporating the concepts of access, use and sustainability, notably by co-designing equipment and supporting stakeholders
Enteric methane emission response to peanut (Arachis hypogaea) and cowpea (Vigna unguiculata) haulms supplementation in zebu cattle diets
Get PDFImproving the quality of ruminant rations is a promising strategy for mitigating the climate impact of livestock farming in West Africa. Legume crop coproducts such as peanut (Arachis hypogaea) and cowpea (Vigna unguiculata) haulms are a high-protein fodder commonly used by agropastoral farmers during the dry season. This study evaluated their potential to reduce enteric methane (eCH4) emissions when used as supplements for Panicum maximum C1 hay. Ten Sudanese Fulani zebu bulls (49 ± 1.2 months; 183.7 ± 15.9 kg) were housed individually and fed 11 diets ad libitum: a control diet of 100% P. maximum and 10 experimental diets combining P. maximum with either peanut or cowpea haulms at ratios of 85:15, 70:30, 55:45, 40:60, and 25:75. Each trial lasted 21 days, comprising a 14-day adaptation period and a 7-day data collection period for feed intake, digestibility, and eCH4 emissions. The latter were measured six times daily using the GreenFeed system. Supplementation increased protein content by 47.5% to 183.5% and ADL by 2.6% to 48.2% while reducing the content of crude fiber, NDF, and ADF. Feed intake increased by 17.8% to 49.1% (p < 0.05), and digestibility improved by 4.6% to 9.9% (p < 0.05). Peanut haulms reduced eCH4 yield by up to 6.1% (p < 0.05), while cowpea haulms achieved reductions of 3.7%–4.8% (p = 0.14). The most effective mitigation was achieved with 75% peanut or 45% cowpea haulms, confirming the potential of legume coproducts to enhance feed efficiency and reduce eCH4 emissions in West African cattle systems
What sort of digitalization do family farmers need?
Get PDFDigitalizing the agricultural sector in West Africa is a promising opportunity for stakeholders in the agricultural and technology sectors, an opportunity that relies on agricultural producers' voluntary mass appropriation of connected phone tools. Mobile phones and app use could foster independent producer networks, improve value chain structuring and boost the sector's economic value. Agricultural producers are now being targeted by a growing number of providers of “digital services”, in the form of apps developed by tech and agritech start-ups. However, apps developed specifically for agricultural producers have met with mixed success. What lessons can be drawn from this mixed bag of results, and what will it take for digitalization to truly serve producers and facilitate the transition to socially, economically and environmentally sustainable practices
¿Cómo digitalizar la agricultura familiar?
Get PDFLa digitalización del sector agrícola en África Occidental promete numerosos beneficios para los actores de las cadenas agrícolas y del sector tecnológico. Estas promesas se basan en la apropiación voluntaria y masiva por parte de los productores agrícolas de herramientas telefónicas conectadas a la red de internet. El uso del teléfono celular y de sus aplicaciones podría favorecer la creación de redes autónomas entre los productores, estructurar mejor las cadenas de valor y aumentar el valor económico del sector. Los productores agrícolas son ahora el objetivo de un número creciente de proveedores de “servicios digitales”, desarrollados en forma de aplicaciones por empresas emergentes de tecnología y agrotecnología. Sin embargo, el éxito de las aplicaciones desarrolladas para los productores agrícolas ha sido desigual. ¿Qué lecciones podemos aprender de este éxito parcial y qué medidas deben tomarse para que los servicios digitales estén plenamente a disposición de los agricultores y facilitar una transición hacia prácticas sostenibles en lo social, económico y ambiental
A new tandem repeat-based genotyping scheme for the global surveillance of Xanthomonas citri pv. mangiferaeindicae, an understudied bacterial pathogen of major importance to mango and cashew production
Get PDFBacterial canker, caused by Xanthomonas citri pv. mangiferaeindicae (Xcm), is a disease that has a devastating impact on mango and cashew industries in many regions. Yet, despite its agricultural importance for these Anacardiaceae species, Xcm has been neglected. Little is known about its epidemiology, evolution and molecular interactions with host plants. The most relevant studies reporting its genetic structure were primarily based on amplified fragment length polymorphism (AFLP) data. This technique provides reliable assessments of the genetic relatedness among bacteria, but is limited in terms of interlaboratory comparisons. Alternative genotyping techniques are required to decipher the global epidemiology and geographic expansion of Xcm. Herein, we screened the genome of the Xcm strain CFBP1716 for tandem repeats. We developed and evaluated the performance of an optimized Multi Locus Variable number of tandem repeat Analysis (MLVA), targeting 16 tandem repeat loci primarily with large repeat units, i.e., minisatellites (MLVA-16). To achieve this, we genotyped a comprehensive collection of 152 Xcm strains, representative of the pathogen's worldwide genetic diversity, together with some reference strains of X. citri pv. anacardii, another genetically-related pathogen of Anacardiaceae. MLVA-16 allowed us to distinguish the two pathovars. Although MLVA-16 was slightly less discriminative than AFLP, the two derived datasets were strongly correlated, suggesting that MLVA-16 provides a good phylogenetic signal. Five clusters with some geographic coherence were delineated, based on discriminant analysis of principal components. The two major clusters grouped strains from multiple geographic origins. In contrast, all strains that have emerged on mango or cashew in West Africa grouped in one cluster, which did not contain any strains of different origin. MLVA-16 represents an opportunity to improve our understanding of the structure of Xcm populations, by sharing genotyping data. The MLVA-16 data generated in this study was deposited in a dedicated online database